Race: a fallacious concept

The current reappearance of the word race to define human biological differences is misleading. It creates social and political problems. In the present synthesis we try to point out the historical responsabilities on the origin of this fallacious concept, and to clarify the misleading overimposition of physical, cultural and religious differences among human populations.     

Photopheresis: a new therapeutic concept

Photopheresis, the process by which peripheral blood is exposed in an extracorporeal flow system to photoactivated 8-methoxypsoralen (8-MOP), is a new treatment for disorders caused by aberrant T lymphocytes. It is now a standard therapy for advanced cutaneous T-cell lymphoma and shows promise in the treatment of two autoimmune disorders, pemphigus vulgaris and progressive systemic sclerosis (scleroderma). Additional diseases for which clinical trials are in progress include multiple sclerosis, organ transplant rejection, rheumatoid arthritis, and AIDS. The mechanism of action appears to involve a "vaccination" against the pathogenic T cells, in a clone-specific manner. Photoactivated 8-MOP initiates a cascade of immunologic events by forming covalent photoadducts with nuclear and cell surface-adherent DNA and possibly with other cellular molecules. For reasons not yet fully clarified, but probably related to enhanced cycling of the T-cell receptor for antigen, photopheresis increases the immunogenicity of the irradiated T cells so that their reinfusion induces a therapeutically significant immunologic reaction that targets unirradiated T cells of the pathogenic clone(s). The specificity of the induced immunologic reaction probably results from the extremely disproportionate expansion of the pathogenic clone(s), relative to the several million other clones of normal T cells.     

Inclusion bodies: a new concept

In the last decades, the understanding of inclusion body biology and consequently, of their properties and potential biotechnological applications have dramatically changed. Therefore, the development of new purification protocols aimed to preserve those properties is becoming a pushing demand.     

Phosphene phenomenon: a new concept

This paper proposes a new biopsychophysical concept of phosphene phenomenon. Namely, visual sensation of phosphenes is due to the intrinsic perception of ultraweak bioluminescent photon emission of cells in the visual system. In other words, phosphenes are bioluminescent biophotons in the visual system induced by various stimuli (mechanical, electrical, magnetic, ionizing radiation, etc.) as well as random bioluminescent biophotons firings of cells in the visual pathway. This biophoton emission can become conscious if induced or spontaneous biophoton emission of cells in the visual system exceeds a distinct threshold. Neuronal biophoton communication can occur by means of non-visual neuronal opsins and natural photosensitive biomolecules. Our interpretation is in direct connection with the functional roles of free radicals and excited biomolecules in living cells.     

Context dependency in biodiversity patterns of central German stream metacommunities

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High-resolution peptide mapping of cerebrospinal fluid: a novel concept for diagnosis and research in central nervous system diseases

Peptides, such as many hormones, cytokines and growth factors play a central role in biological processes. Furthermore, as degradation products and processed forms of larger proteins they are part of the protein turnover. Thus, they can reflect disease-related changes in an organism's homeostasis in several ways. Since two-dimensional gel electrophoresis is restricted to analysis and display of proteins with relative molecular masses above 5000, we developed Differential Peptide Display (DPD), a new technology for analysis and visualization of peptides. Here we describe its application to cerebrospinal fluid of three subjects without a disease of the central nervous system (CNS) undergoing routine myelography and of two patients suffering from a primary CNS lymphoma. Peptides with a relative molecular mass below 20000 were extracted and analysed by a combination of chromatography and mass spectrometry. The peptide pattern of a sample was depicted as a multi-dimensional peptide mass fingerprint with each peptide's position being characterized by its molecular mass and chromatographic behaviour. Such a fingerprint of a CNS sample consists of more than 6000 different signals. Data analysis of peptide patterns from patients with CNS lymphoma compared to controls revealed obvious differences regarding the peptide content of the samples. By analysing peptides within a mass range of 750-20000, DPD extends 2D gel electrophoresis, thus offering the chance to investigate CNS diseases on the level of peptides. This represents a new approach for diagnosis and possible therapy.     

Probiotics: a therapeutic concept awaiting recognition

The history of emergence of the probiotics concept as well as basic knowledge on the mechanism of their action is described. The possibilities of the therapeutic use of probiotics, in particular for cases of Crohn's disease, viral gastroenteritis and travelers' diarrhea are discussed. The conclusion is made that the effectiveness of the use of probiotics has not yet been proved due to the fact that in clinical trials of these preparations many uncontrolled variables are not taken into consideration. For this reason at the present moment the prophylactic and curative use of probiotics is an idea whose constructive character has yet to be proved.     

The receptor concept: a continuing evolution

This review briefly summarizes the development of the receptor concept, the identification of receptors based first on biological response data and subsequently on radioligand binding properties, and the biological and physiological understandings that these approaches have made possible. The development of receptor characterization began with receptors that ultimately were discovered to mediate response by coupling to G-binding proteins, also known as G protein-coupled receptors (GPCRs). Consequently, many if not all of the examples in this overview will describe studies characterizing GPCRs in general, and adrenergic receptors in particular. The purpose of this review, however, is not a detailed chronological account of a huge literature, but rather an overview of the fundamental questions posed and answered by these studies.     

Racialization: a defense of the concept

This paper defends the concept of racialization against its critics. As the concept has become increasingly popular, questions about its meaning and value have been raised, and a backlash against its use has occurred. I argue that when “racialization” is properly understood, criticisms of the concept are unsuccessful. I defend a definition of racialization and identify its companion concept, “racialized group.” Racialization is often used as a synonym for “racial formation.” I argue that this is a mistake. Racial formation theory is committed to racial ontology, but racialization is best understood as the process through which racialized – rather than racial – groups are formed. “Racialization” plays a unique role in the conceptual landscape, and it is a key concept for race eliminativists and anti-realists about race.     

Field homology: a meaningless concept.

Most biological homologues involve comparison of single characters in two or more taxa. It is possible, however, to recognize homologous characters between two or more taxa that involve the transformation of one character into many characters or many characters into one character. This type of homology is recognized as field homology and it has been widely used in comparative neuroanatomy. The emergence of the cladistic analysis of embryonic stages in the development of neural characters, however, strongly suggests that field homology is a meaningless concept. When it appears necessary to recognize field homologues, it is because comparisons are being made at an inappropriate level within a given biological hierarchy. Furthermore, recognition of field homologues restricts evolutionary mechanisms to a single mechanism of parcellation as defined by Ebbesson.     

A reconsideration of the central pattern generator concept for locust flight

Summary Although it is generally agreed that locusts can generate flight similar rhythmic motor activity in the absence of sensory feedback from the wings, recent studies indicate that functional deafferentation produces significant changes in the flight motor pattern (Hedwig and Pearson 1984). These findings have raised doubts on the adequacy of the central pattern generator concept for the locust flight system (Pearson 1985). In this paper, we re-investigate the effects of deafferentation on the capacity of adult migratory locusts to generate the flight motor pattern. For this purpose, the experimental animals were dissected to various degrees, ranging from head-ventral nerve cord, to isolated pterothoracic nerve cord, and finally single isolated ganglion preparations. Flight motor activity was released by either wind stimulation, the more traditional method, or by applying octopamine (Sombati and Hoyle 1984; Stevenson and Kutsch 1986). In all cases the released motor activity was analysed, giving details of latency, and phase relationships between specific synergistic and antagonistic motor units, and then compared with the flight motor pattern generated by intact tethered locusts.This analysis shows that deafferentation, although reducing the frequency, does not necessarily disrupt the basic flight motor pattern. By using octopamine we could show that even isolated thoracic nerve cord preparations can generate activity, which in all major aspects corresponds to this motor program. This could also be shown for the fully isolated metathoracic ganglion and we provide some evidence that the mesothoracic ganglion may be capable of a similar performance. In addition to releasing flight activity, octopamine was also found to enhance the responsiveness of deafferentated locusts to wind stimulation. This resulted in a considerable elevation of the frequency and prolongation of the flight motor activity to values comparable to the performance of intact tethered locusts.     

Race: a social destruction of a biological concept

It is nowadays a dominant opinion in a number of disciplines (anthropology, genetics, psychology, philosophy of science) that the taxonomy of human races does not make much biological sense. My aim is to challenge the arguments that are usually thought to invalidate the biological concept of race. I will try to show that the way “race” was defined by biologists several decades ago (by Dobzhansky and others) is in no way discredited by conceptual criticisms that are now fashionable and widely regarded as cogent. These criticisms often arbitrarily burden the biological category of race with some implausible connotations, which then opens the path for a quick eliminative move. However, when properly understood, the biological notion of race proves remarkably resistant to these deconstructive attempts. Moreover, by analyzing statements of some leading contemporary scholars who support social constructivism about race, I hope to demonstrate that their eliminativist views are actually in conflict with what the best contemporary science tells us about human genetic variation.     

ADHD in adults: a concept in evolution

Although attention-deficit/hyperactivity disorder (ADHD) has been recognized as a disorder affecting individuals across the life cycle since the end of the nineties, there is still considerable debate on how to conceptualize the disorder in adults, and on the best way to operationalize diagnostic criteria for this age range. In this comprehensive non-systematic review of the literature, we provide data about prevalence and presentation of ADHD in adulthood as well as discuss major problems in applying criteria developed for children in assessing adults (clinical utility, threshold of symptoms for diagnosis, full ADHD diagnosis in childhood, information source, and additional dimensions for diagnosis-executive functioning impairment and emotional impulsivity). In addition, we provide some recommendations for improving ADHD diagnostic criteria in adulthood.